For the first time, a drug has helped prevent heart attacks by curbing inflammation, a new and very different approach than lowering cholesterol, the focus for many years.

People on the drug also had surprisingly lower cancer death rates, especially from lung cancer. An anti-tumor effect is an exciting possibility, but it needs much more study because the heart experiment wasn’t intended to test that.

Doctors say the results on the drug, canakinumab, open a new frontier. Many heart attacks occur in people whose cholesterol is normal and whose main risk is chronic inflammation that can lead to clogged arteries.

“We suddenly know we can address the inflammation itself, the same way we learned almost 25 years ago that we could address cholesterol. It’s very exciting,” said the study’s leader, Dr. Paul Ridker of Brigham and Women’s Hospital in Boston.

Results were published Sunday by the New England Journal of Medicine and Lancet, and presented at the European Society of Cardiology conference in Barcelona, Spain. The drug’s maker, Novartis, sponsored the study and Ridker consults for the company.

Statins such as Lipitor lower LDL or bad cholesterol and have been the cornerstone of preventing heart attacks along with not smoking, blood pressure control and a healthy lifestyle.

Yet one quarter of people who suffer a heart attack will have another one within five years, and inflammation is a culprit in half of those cases.

Inflammation happens after a joint is injured and swells, but similar chemical responses can occur over time throughout the body with unhealthy habits. That chronic, unseen inflammation can damage arteries and set the stage for clots.

Twenty years ago, Ridker helped clarify its role and patented a cheap blood test for a sign of inflammation called high-sensitivity C-reactive protein, or CRP.

Canakinumab lowers CRP and is sold now under the brand name Ilaris for some rare inherited diseases.

The study tested it in 10,000 heart attack survivors with low cholesterol but high CRP. They got the usual heart medicines including statins and were given one of three different doses of canakinumab or a placebo as a shot every three months.

Those on the medium dose had a 15 percent lower chance of another heart attack, a stroke or a heart-related death over the next four years compared to people given dummy shots. About 33 people would have to be treated for five years to prevent one of these problems — a ratio that outside experts called very good.